Methods to partially reduce a niobium metal oxide and oxygen reduced niobium oxides

ABSTRACT

Methods to at least partially reduce a niobium oxide are described wherein the process includes heat treating the niobium oxide in the presence of a getter material and in an atmosphere which permits the transfer of oxygen atoms from the niobium oxide to the getter material, and for a sufficient time and at a sufficient temperature to form an oxygen reduced niobium oxide. Niobium oxides and/or suboxides are also described as well as capacitors containing anodes made from the niobium oxides and suboxides.

[0001] This application is a divisional of U.S. patent application Ser.No. 09/154,452 filed Sep. 16, 1998, which is incorporated herein intheir entirety by reference.

BACKGROUND OF THE INVENTION

[0002] The present invention relates to niobium and oxides thereof andmore particularly relates to niobium oxides and methods to at leastpartially reduce niobium oxide and further relates to oxygen reducedniobium.

SUMMARY OF THE PRESENT INVENTION

[0003] In accordance with the purposes of the present invention, asembodied and described herein, the present invention relates to a methodto at least partially reduce a niobium oxide which includes the steps ofheat treating the niobium oxide in the presence of a getter material andin an atmosphere which permits the transfer of oxygen atoms from theniobium oxide to the getter material for a sufficient time andtemperature to form an oxygen reduced niobium oxide.

[0004] The present invention also relates to oxygen reduced niobiumoxides which preferably have beneficial properties, especially whenformed into an electrolytic capacitor anode. For instance, a capacitormade from the oxygen reduced niobium oxide of the present invention canhave a capacitance of up to about 200,000 CV/g or more. Further,electrolytic capacitor anodes made from the oxygen reduced niobiumoxides of the present invention can have a low DC leakage. For instance,such a capacitor can have a DC leakage of from about 0.5 nA/CV to about5.0 nA/CV.

[0005] Accordingly, the present invention also relates to methods toincrease capacitance and reduce DC leakage in capacitors made fromniobium oxides, which involves partially reducing a niobium oxide byheat treating the niobium oxide in the presence of a getter material andin an atmosphere which permits the transfer of oxygen atoms from theniobium oxide to the getter material, for a sufficient time andtemperature to form an oxygen reduced niobium oxide, which when formedinto a capacitor anode, has reduced DC leakage and/or increasedcapacitance.

[0006] It is to be understood that both the foregoing generaldescription and the following detailed description are exemplary andexplanatory only and are intended to provide further explanation of thepresent invention, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] FIGS. 1-11 are SEMs of various oxygen reduced niobium oxides ofthe present invention at various magnifications.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

[0008] In an embodiment of the present invention, the present inventionrelates to methods to at least partially reduce a niobium oxide. Ingeneral, the method includes the steps of heat treating a startingniobium oxide in the presence of a getter material in an atmospherewhich permits the transfer of oxygen atoms from the niobium oxide to thegetter material for a sufficient time and at a sufficient temperature toform an oxygen reduced niobium oxide.

[0009] For purposes of the present invention, the niobium oxide can beat least one oxide of niobium metal and/or alloys thereof. A specificexample of a starting niobium oxide is Nb₂O₅.

[0010] The niobium oxide used in the present invention can be in anyshape or size. Preferably, the niobium oxide is in the form of a powderor a plurality of particles. Examples of the type of powder that can beused include, but are not limited to, flaked, angular, nodular, andmixtures or variations thereof. Preferably, the niobium oxide is in theform of a powder which more effectively leads to the oxygen reducedniobium oxide.

[0011] Examples of such preferred niobium oxide powders include thosehaving mesh sizes of from about {fraction (60/100)} to about {fraction(100/325)} mesh and from about {fraction (60/100)} to about {fraction(200/325)} mesh. Another range of size is from −40 mesh to about −325mesh.

[0012] The getter material for purposes of the present invention is anymaterial capable of reducing the specific starting niobium oxide to theoxygen reduced niobium oxide. Preferably, the getter material comprisestantalum, niobium, or both. More preferably, the getter material istantalum. The tantalum getter material for purposes of the presentinvention is any material containing tantalum metal which can remove orreduce at least partially the oxygen in the niobium oxide. Thus, thetantalum getter material can be an alloy or a material containingmixtures of tantalum metal with other ingredients. Preferably, thetantalum getter material is predominantly, if not exclusively, tantalummetal. The purity of the tantalum metal is not important but it ispreferred that high purity tantalum metal comprise the getter materialto avoid the introduction of other impurities during the heat treatingprocess. Accordingly, the tantalum metal in the tantalum getter materialpreferably has a purity of at least about 98% and more preferably atleast about 99%. Further, it is preferred that impurities such as oxygenare not present or are present in amounts below about 100 ppm.

[0013] The getter material can be in any shape or size. For instance,the getter material can be in the form of a tray which contains theniobium oxide to be reduced or can be in a particle or powder size.Preferably, the getter materials are in the form of a powder in order tohave the most efficient surface area for reducing the niobium oxide. Thegetter material, thus, can be flaked, angular, nodular, and mixtures orvariations thereof. Preferably, the getter material is a tantalumhydride material. A preferred form is coarse chips, e.g., {fraction(14/40)} mesh chips that can be easily separated from the powder productby screening.

[0014] Similarly, the getter material can be niobium and the like andcan have the same preferred parameters and/or properties discussed abovefor the tantalum getter material. Other getter materials can be usedalone or in combination with the tantalum or niobium getter materials.Also, other materials can form a part of the getter material.

[0015] Generally, a sufficient amount of getter material is present toat least partially reduce the niobium oxide being heat treated. Further,the amount of the getter material is dependent upon the amount ofreducing desired to the niobium oxide. For instance, if a slightreduction in the niobium oxide is desired, then the getter material willbe present in a stoichemetric amount. Similarly, if the niobium oxide isto be reduced substantially with respect to its oxygen presence, thenthe getter material is present in a 2 to 5 times stoichemetric amount.Generally, the amount of getter material present (e.g., based on thetantalum getter material being 100% tantalum) can be present based onthe following ratio of getter material to the amount of niobium oxidepresent of from about 2 to 1 to about 10 to 1.

[0016] Furthermore, the amount of getter material can also be dependenton the type of niobium oxide being reduced. For instance, when theniobium oxide being reduced is Nb₂O₅, the amount of getter material ispreferably 5 to 1.

[0017] The heat treating that the starting niobium oxide is subjected tocan be conducted in any heat treatment device or furnace commonly usedin the heat treatment of metals, such as niobium and tantalum. The heattreatment of the niobium oxide in the presence of the getter material isat a sufficient temperature and for a sufficient time to form an oxygenreduced niobium oxide. The temperature and time of the heat treatmentcan be dependent on a variety of factors such as the amount of reductionof the niobium oxide, the amount of the getter material, and the type ofgetter material as well as the type of starting niobium oxide.Generally, the heat treatment of the niobium oxide will be at atemperature of from less than or about 800° C. to about 1900° C. andmore preferably from about 1000° C. to about 1400° C., and mostpreferably from about 1200° C. to about 1250° C. In more detail, whenthe niobium oxide is a niobium containing oxide, the heat treatmenttemperatures will be from about 1000° C. to about 1300° C., and morepreferably from about 1200° C. to about 1250° C. for a time of fromabout 5 minutes to about 100 minutes, and more preferably from about 30minutes to about 60 minutes. Routine testing in view of the presentapplication will permit one skilled in the art to readily control thetimes and temperatures of the heat treatment in order to obtain theproper or desired reduction of the niobium oxide.

[0018] The heat treatment occurs in an atmosphere which permits thetransfer of oxygen atoms from the niobium oxide to the getter material.The heat treatment preferably occurs in a hydrogen containing atmospherewhere is preferably just hydrogen. Other gases can also be present withthe hydrogen, such as inert gases, so long as the other gases do notreact with the hydrogen. Preferably, the hydrogen atmosphere is presentduring the heat treatment at a pressure of from about 10 Torr to about2000 Torr, and more preferably from about 100 Torr to about 1000 Torr,and most preferably from about 100 Torr to about 930 Torr. Mixtures ofH₂ and an inert gas such as Ar can be used. Also, H₂ in N₂ can be usedto effect control of the N₂ level of the niobium oxide.

[0019] During the heat treatment process, a constant heat treatmenttemperature can be used during the entire heat treating process orvariations in temperature or temperature steps can be used. Forinstance, hydrogen can be initially admitted at 1000° C. followed byincreasing the temperature to 1250° C. for 30 minutes followed byreducing the temperature to 1000° C. and held there until removal of theH₂ gas. After the H₂ or other atmosphere is removed, the furnacetemperature can be dropped. Variations of these steps can be used tosuit any preferences of the industry.

[0020] The oxygen reduced niobium oxides can also contain levels ofnitrogen, e.g., from about 100 ppm to about 30,000 ppm N₂.

[0021] The oxygen reduced niobium oxide is any niobium oxide which has alower oxygen content in the metal oxide compared to the starting niobiumoxide. Typical reduced niobium oxides comprise NbO, NbO_(0.7),NbO_(1.1), NbO₂, and any combination thereof with or without otheroxides present. Generally, the reduced niobium oxide of the presentinvention has an atomic ratio of niobium to oxygen of about 1:less than2.5, and preferably 1:2 and more preferably 1:1.1, 1:1, or 1:0.7. Putanother way, the reduced niobium oxide preferably has the formulaNb_(x)O_(y), wherein Nb is niobium, x is 2 or less, and y is less than2.5x. More preferably x is 1 and y is less than 2, such as 1.1, 1.0,0.7, and the like.

[0022] The starting niobium oxides can be prepared by calcining at 1000°C. until removal of any volatile components. The oxides can be sized byscreening. Preheat treatment of the niobium oxides can be used to createcontrolled porosity in the oxide particles.

[0023] The reduced niobium oxides of the present invention alsopreferably have a microporous surface and preferably have a sponge-likestructure, wherein the primary particles are preferably 1 micron orless. The SEMs further depict the type of preferred reduced niobiumoxide of the present invention. As can be seen in thesemicrophotographs, the reduced niobium oxides of the present inventioncan have high specific surface area, and a porous structure withapproximately 50% porosity. Further, the reduced niobium oxides of thepresent invention can be characterized as having a preferred specificsurface area of from about about 0.5 to about 10.0 m²/g, more preferablyfrom about 0.5 to 2.0 m²/g, and even more preferably from about 1.0 toabout 1.5 m²/g. The preferred apparent density of the powder of theniobium oxides is less than about 2.0 g/cc, more preferably, less than1.5 g/cc and more preferably, from about 0.5 to about 1.5 g/cc.

[0024] The various oxygen reduced niobium oxides of the presentinvention can be further characterized by the electrical propertiesresulting from the formation of a capacitor anode using the oxygenreduced niobium oxides of the present invention. In general, the oxygenreduced niobium oxides of the present invention can be tested forelectrical properties by pressing powders of the oxygen reduced niobiumoxide into an anode and sintering the pressed powder at appropriatetemperatures and then anodizing the anode to produce an electrolyticcapacitor anode which can then be subsequently tested for electricalproperties.

[0025] Accordingly, another embodiment of the present invention relatesto anodes for capacitors formed from the oxygen reduced niobium oxidesof the present invention. Anodes can be made from the powdered form ofthe reduced oxides in a similar process as used for fabricating metalanodes, i.e., pressing porous pellets with embedded lead wires or otherconnectors followed by optional sintering and anodizing. The leadconnector can be embedded or attached at any time before anodizing.Anodes made from some of the oxygen reduced niobium oxides of thepresent invention can have a capacitance of from about 1,000 CV/g orlower to about 300,000 CV/g or more, and other ranges of capacitance canbe from about 20,000 CV/g to about 300,000 CV/g or from about 62,000CV/g to about 200,000 CV/g and preferably from about 60,000 to 150,000CV/g. In forming the capacitor anodes of the present invention, asintering temperature can be used which will permit the formation of acapacitor anode having the desired properties. The sintering temperaturewill be based on the oxygen reduced niobium oxide used. Preferably, thesintering temperature is from about 1200° C. to about 1750° C. and morepreferably from about 1200° C. to about 1400° C. and most preferablyfrom about 1250° C. to about 1350° C. when the oxygen reduced niobiumoxide is an oxygen reduced niobium oxide.

[0026] The anodes formed from the niobium oxides of the presentinvention are preferably formed at a voltage of about 35 volts andpreferably from about 6 to about 70 volts. When an oxygen reducedniobium oxide is used, preferably, the forming voltages are from about 6to about 50 volts, and more preferably from about 10 to about 40 volts.Other high formation voltages can be used. Anodes of the reduced niobiumoxides can be prepared by fabricating a pellet of Nb₂O₅ with a lead wirefollowed by sintering in H₂ atmosphere or other suitable atmosphere inthe proximity of a getter material just as with powdered oxides. In thisembodiment, the anode article produced can be produced directly, e.g.,forming the oxygen reduced valve metal oxide and an anode at the sametime. Also, the anodes formed from the oxygen reduced niobium oxides ofthe present invention preferably have a DC leakage of less than about5.0 nA/CV. In an embodiment of the present invention, the anodes formedfrom some of the oxygen reduced niobium oxides of the present inventionhave a DC leakage of from about 5.0 nA/CV to about 0.50 nA/CV.

[0027] The present invention also relates to a capacitor in accordancewith the present invention having a niobium oxide film on the surface ofthe capacitor. Preferably, the film is a niobium pentoxide film. Themeans of making metal powder into capacitor anodes is known to thoseskilled in the art and such methods such as those set forth in U.S. Pat.Nos. 4,805,074, 5,412,533, 5,211,741, and 5,245,514, and EuropeanApplication Nos. 0 634 762 A1 and 0 634 761 A1, all of which areincorporated in their entirety herein by reference.

[0028] The capacitors of the present invention can be used in a varietyof end uses such as automotive electronics, cellular phones, computers,such as monitors, mother boards, and the like, consumer electronicsincluding TVs and CRTs, printers/copiers, power supplies, modems,computer notebooks, disc drives, and the like.

[0029] The present invention will be further clarified by the followingexamples, which are intended to be exemplary of the present invention.Anode Fabrication size - 0.197″ dia 3.5 Dp powder wt = 341 mg AnodeSintering 1300 Deg C.* 10′ 1450 Deg C.* 10′ 1600 Deg C.* 10′ 1750 DegC.* 10′ 30 V Ef Anodization 30 V Ef @ 60 Deg C./0.1% H₃PO₄ Electrolyte20 mA/g constant current DC Leakage/Capacitance - ESR Testing: DCLeakage Testing --- 70% Ef (21 VDC) Test Voltage 60 second charge time10% H₃PO₄ @ 21 Deg C. Capacitance - DF Testing: 18% H₂SO₄ @ 21 Deg C.120 Hz 50 V Ef Reform Anodization 50 V Ef @ 60 Deg C./0.1% H₃PO₄Electrolyte 20 mA/g constant current DC Leakage/Capacitance - ESRTesting DC leakage Testing --- 70% Ef(35 VDC) Test Voltage 60 secondcharge time 10% H₃PO₄ @ 21 Deg C. Capacitance - DF Testing: 18% H₂SO₄ @21 Deg C. 120 Hz 75 V Ef Reform Anodization 75 V Ef @ 60 Deg C./0.1%H₃PO₄ Electrolyte 20 mA/g constant current DC. Leakage/Capacitance - ESRTesting DC leakage Testing --- 70% Ef (52.5 VDC) Test Voltage 60 secondcharge time 10% H₃PO₄ @ 21 Deg C. Capacitance - DF Testing: 18% H₂SO₄ @21 DegC. 120 Hz

[0030] Scott Density, oxygen analysis, phosphorus analysis, and BETanalysis were determined according to the procedures set forth in U.S.Pat. Nos. 5,011,742; 4,960,471; and 4,964,906, all incorporated herebyin their entireties by reference herein.

EXAMPLES Example 1

[0031] +10 mesh Ta hydride chips (99.2 gms) with approximately 50 ppmoxygen were mixed with 22 grams of Nb₂O₅ and placed into Ta trays. Thetrays were placed into a vacuum heat treatment furnace and heated to1000° C. H₂ gas was admitted to the furnace to a pressure of +3psi. Thetemperature was further ramped to 1240° C. and held for 30 minutes. Thetemperature was lowered to 1050° C. for 6 minutes until all H₂ was sweptfrom the furnace. While still holding 1050° C., the argon gas wasevacuated from the furnace until a pressure of 5×10⁻⁴ torr was achieved.At this point 700 mm of argon was readmitted to the chamber and thefurnace cooled to 60° C.

[0032] The material was passivated with several cyclic exposures toprogressively higher partial pressures of oxygen prior to removal fromthe furnace as follows: The furnace was backfilled with argon to 700 mmfollowed by filling to one atmosphere with air. After 4 minutes thechamber was evacuated to 10⁻² torr. The chamber was then backfilled to600 mm with argon followed by air to one atmosphere and held for 4minutes. The chamber was evacuated to 10⁻² torr. The chamber was thenbackfilled to 400 mm argon followed by air to one atmosphere. After 4minutes the chamber was evacuated to 10⁻² torr. The chamber was thembackfilled to 200 mm argon followed by air to one atmosphere and heldfor 4 minutes. The chamber was evacuated to 10⁻² torr. The chamber wasbackfilled to one atmosphere with air and held for 4 minutes. Thechamber was evacuated to 10⁻² torr. The chamber was backfilled to oneatmosphere with argon and opened to remove the sample.

[0033] The powder product was separated from the tantalum chip getter byscreening through a 40 mesh screen. The product was tested with thefollowing results.

[0034] CV/g of pellets sintered to 1300° C.×10 minutes and formed to 35

[0035] volts=81,297

[0036] nA/CV (DC leakage)=5.0

[0037] Sintered Density of pellets=2.7 g/cc

[0038] Scott density=0.9 g/cc

[0039] Chemical Analysis (ppm) C = 70 H₂ = 56 Ti = 25 Fe = 25 Mn = 10 Si= 25 Sn = 5 Ni = 5 Cr = 10 Al = 5 Mo = 25 Mg = 5 Cu = 50 B = 2 Pb = 2all others <limits

Example 2

[0040] Samples 1 through 20 are examples following similar steps asabove with powdered Nb₂O₅ as indicated in the Table. For most of theexamples, mesh sizes of the starting input material are set forth in theTable, for example {fraction (60/100)}, means smaller than 60 mesh, butlarger than 100 mesh. Similarly, the screen size of some of the Tagetter is given as {fraction (14/40)}. The getters marked as “Ta hydridechip” are +40 mesh with no upper limit on particle size.

[0041] Sample 18 used Nb as the getter material (commercially availableN200 flaked Nb powder from CPM). The getter material for sample 18 wasfine grained Nb powder which was not separated from the final product.X-ray diffraction showed that some of the getter material remained asNb, but most was converted to NbO_(1.1) and NbO by the process as wasthe starting niobium oxide material Nb₂O₅.

[0042] Sample 15 was a pellet of Nb₂O₅, pressed to near solid density,and reacted with H₂ in close proximity to the Ta getter material. Theprocess converted the solid oxide pellet into a porous slug of NbOsuboxide. This slug was sintered to a sheet of Nb metal to create ananode lead connection and anodized to 35 volts using similar electricalforming procedures as used for the powder slug pellets. This sampledemonstrates the unique ability of this process to make a ready toanodize slug in a single step from Nb₂O₅ starting material.

[0043] The Table shows the high capacitance and low DC leakage capableof anodes made from the pressed and sintered powders/pellets of thepresent invention. Microphotographs (SEMs) of various samples weretaken. These photographs show the porous structure of the reduced oxygenniobium oxide of the present invention. In particular, FIG. 1 is aphotograph of the outer surface of a pellet taken at 5,000× (sample 15).FIG. 2 is a photograph of the pellet interior of the same pellet takenat 5,000×. FIGS. 3 and 4 are photographs of the outer surface of thesame pellet at 1,000×. FIG. 5 is a photograph of sample 11 at 2,000× andFIGS. 6 and 7 are photographs taken of sample 4 at 5,000×. FIG. 8 is aphotograph taken of sample 3 at 2,000× and FIG. 9 is a photograph ofsample 6 at 2,000×. Finally, FIG. 10 is a photograph of sample 6, takenat 3,000× and FIG. 11 is a photograph of sample 9 taken at 2,000×. TABLEXRD* XRD* XRD* XRD* Sam- Temp Time Hydrogen Major Major Minor Minor1300X35v 1300X35v ple Input Material Gms Input Getter GMS (° C.) (min)Pressure 1** 2** 1*** 2*** CV/g na/CV 1 40 mesh 20 (est) Ta hydridechips 40 (est) 1240 30 3 psi 81297 5 calcined Nb₂O₅ 2 60/100 Nb₂O₅ 23.4Ta hydride chips 65.4 1250 30 3 psi NbO₁₁ NbO TaO 115379 1.28 3 60/100Nb₂O₅ 23.4 Ta hydride chips 65.4 1250 30 3 psi NbO₁₁ NbO TaO 121293 2.194 100/325 Nb₂O₅ 32.3 Ta hydride chips 92.8 1250 30 3 psi 113067 1.02 5100/325 Nb₂O₅ 32.3 Ta hydride chips 92.8 1250 30 3 psi 145589 1.42 660/100 Nb₂O₅ 26.124 Ta hydride chips 72.349 1250 90 3 psi 17793 12.86 760/100 Nb₂O₅ 26.124 Ta hydride chips 72.349 1250 90 3 psi 8 200/325Nb₂O₅ 29.496 Ta hydride chips 83.415 1250 90 3 psi 17790 16.77 9 60/100Nb₂O₅ 20.888 Ta hydride chips 60.767 1200 90 3 psi NbO₁₁ NbO Ta₂O₅ 632575.17 10 60/100 Nb₂O₅ 20.888 Ta hydride chips 60.767 1200 90 3 psi NbO₁₁NbO Ta₂O₅ 69881 5.5 11 200/325 Nb₂O₅ 23.396 Ta hydride chips 69.266 120090 3 psi NbO₁₁ NbO Ta₂O₅ 61716 6.65 12 200/325 Nb₂O₅ 23.936 Ta hydridechips 69.266 1200 90 3 psi NbO₁₁ NbO Ta₂O₅ 68245 6.84 13 200/325 Nb₂O₅15.5 14/40 Ta hydride 41.56 1250 30 3 psi NbO₀₇ NbO TaO NbO₂ 76294 4.0314 200/325 Nb₂O₅ 10.25 14/40 Ta hydride 68.96 1250 30 3 psi NbO₀₇ NbOTaO NbO₂ 29281 21.03 15 Nb₂O₅ pellets  3.49 14/40 Ta hydride 25.7 125030 3 psi 70840 0.97 16 200/325 Nb₂O₅ 13.2 14/40 Ta hydride 85.7 1200 303 psi NbO₂ NbO₀₇ TaO NbO 5520 34.33 17 200/325 Nb₂O₅ 14.94 14/40 Tahydride 41.37 1200 30 3 psi 6719 38.44 18 200/325 Nb₂O₅ 11.92 N200 Nbpowder 21.07 1200 30 3 psi Nb NbO₁₁ NbO 25716 4.71 19 200/325 Nb₂O₅ 1014/40 Ta hydride 69 1250 30 100 Torr 108478 1.95 20 200/325 Nb₂O₅ 1614/40 Ta hydride 41 1250 30 100 Torr 106046 1.66

[0044] Other embodiments of the present invention will be apparent tothose skilled in the art from consideration of the specification andpractice of the invention disclosed herein. It is intended that thespecification and examples be considered as exemplary only, with a truescope and spirit of the invention being indicated by the followingclaims.

What is claimed is:
 1. A method to at least partially reduce a niobiumoxide comprising heat treating the niobium oxide in the presence of agetter material and in an atmosphere which permits the transfer ofoxygen atoms from the niobium oxide to the getter material, for asufficient time and temperature to form an oxygen reduced niobium oxide.2. The method of claim 1, wherein the niobium oxide is a niobiumpentoxide.
 3. The method of claim 1, wherein the oxygen reduced niobiumoxide is a niobium suboxide.
 4. The method of claim 1, wherein theoxygen reduced niobium oxide has a niobium to oxygen atomic ratio of1:less than 2.5.
 5. The method of claim 1, wherein the oxygen reducedniobium oxide has oxygen levels that are less than stoichemetric for afully oxidized niobium.
 6. The method of claim 1, wherein the oxygenreduced niobium oxide has a microporous structure.
 7. The method ofclaim 1, wherein the oxygen reduced niobium oxide has a pore volume ofabout 50%.
 8. The method of claim 1, wherein the hydrogen atmosphere ispresent in an amount of about 10 Torr to about 2000 Torr.
 9. The methodof claim 1, wherein the getter material comprises tantalum hydrideparticles.
 10. The method of claim 1, wherein the atmosphere is ahydrogen atmosphere.
 11. The method of claim 1, wherein the gettermaterial comprises tantalum, niobium, or both.
 12. The method of claim1, wherein the getter material is {fraction (14/40)} mesh tantalumhydride particles.
 13. The method of claim 1, wherein said heat treatingis at a temperature of from about 1000° C. to about 1300° C. and forabout 10 to about 90 minutes.
 14. The method of claim 1, wherein saidgetter material is tantalum.
 15. A niobium oxide having an atomic ratioof niobium to oxygen of 1:less than 2.5.
 16. The niobium oxide of claim15, wherein the atomic ratio is 1:less than 2.0.
 17. The niobium oxideof claim 15, wherein the atomic ratio is 1:less than 1.5.
 18. Theniobium oxide of claim 15, wherein the atomic ratio is 1:1.1.
 19. Theniobium oxide of claim 15, wherein the atomic ratio is 1:0.7.
 20. Theniobium oxide of claim 15, wherein the atomic ratio is 1:0.5.
 21. Theniobium oxide of claim 15, wherein said niobium oxide has a porousstructure.
 22. The niobium oxide of claim 15, wherein said niobium oxidehas a porous structure having from about 0.1 to about 10 micrometerpores.
 23. The niobium oxide of claim 15, wherein said niobium oxidecomprises NbO, NbO_(0.7), NbO_(1.1), or combinations thereof.
 24. Theniobium oxide of claim 15, wherein said niobium oxide is formed into anelectrolytic capacitor anode having a capacitance of up to about 300,000CV/g.
 25. The niobium oxide of claim 15, further comprising nitrogen.26. The niobium oxide of claim 15, wherein said nitrogen is present inthe amount of from about 100 ppm to about 30,000 ppm N₂.
 27. The niobiumoxide of claim 15, wherein said niobium oxide is formed into anelectrolytic capacitor anode, said anode having a capacitance of fromabout 1,000 to about 300,000 CV/g.
 28. The niobium oxide of claim 27,wherein said capacitance is from about 60,000 to about 200,000 CV/g. 29.The niobium oxide of claim 15, wherein said anode has a DC leakage offrom about 0.5 to about 5 nA/CV.
 30. The niobium oxide of claim 15,wherein said niobium comprises nodular, flaked, angular, or combinationsthereof.
 31. A capacitor comprising the niobium oxide of claim
 15. 32. Acapacitor comprising the niobium oxide of claim
 27. 33. The niobiumoxide of claim 25, wherein said niobium oxide is sintered at atemperature of from about 1200° C. to about 1750° C.
 34. The niobiumoxide of claim 27, wherein said niobium oxide is sintered at atemperature of from about 1200° C. to about 1450° C.
 35. The capacitorof claim 31, having a capacitance of from about 1,000 CV/g to about300,000 CV/g.
 36. The capacitor of claim 31, having a capacitance offrom about 60,000 CV/g to about 200,000 CV/g.
 37. The capacitor of claim31, having a DC leakage of from about 0.5 to about 5 nA/CV.
 38. Thecapacitor of claim 36, having a DC leakage of from about 0.5 to about 5nA/CV.
 39. A method of making a capacitor anode comprising a)fabricating a pellet of niobium oxide and heat treating the pellet inthe presence of a getter material, and in an atmosphere which permitsthe transfer of oxygen atoms from the niobium oxide to the gettermaterial, and for a sufficient time and temperature to form an electrodebody comprising the pellet, wherein the pellet comprises an oxygenreduced niobium oxide, and b) anodizing said electrode body to form saidcapacitor anode.
 40. The method of claim 39, wherein the atmosphere is ahydrogen atmosphere.
 41. The method of claim 39, wherein the gettermaterial comprises tantalum, niobium, or both.
 42. The method of claim39, wherein the getter material is tantalum.
 43. The method of claim 39,wherein the oxygen reduced niobium oxide has an atomic ratio of niobiumto oxygen of 1:less than 2.5.